Finally found the time to do a short writeup on my favorite budget DD IEMs of 2018, the HIFI WALKER A1. While the JVC FD01 are currently my favorite DDs regardless of price, the HW A1 cost only about 50 dollars/euros and still offer highly competitive sound quality when modded. I consider these a great buy and an upgrade over both my former budget favorites, the Fostex TE-02n and Blitzwolf BW-ES1. The HW A1 are available from several Amazon sites: US: https://www.amazon.com/HIFI-WALKER-Resolution-Headphones-Attenuation/dp/B077ZYP7H9 Canada: https://www.amazon.ca/Resolution-Headphones-Earphones-Attenuation-Microphone/dp/B077ZYP7H9 UK: https://www.amazon.co.uk/HIFI-WALKER-A1-Resolution-Attenuation-metallic/dp/B0734JHX1N France: https://www.amazon.fr/HIFI-WALKER-A1-intra-auriculaires-atténuation/dp/B0734JHX1N Italy: https://www.amazon.it/HIFI-WALKER-intrauricolari-risoluzione-attenuazione/dp/B0734JHX1N Germany: https://www.amazon.de/HIFI-WALKER-Hochauflösende-Ear-Kopfhörer-Geräuschdämpfung-Metallisch/dp/B0734JHX1N Japan: https://www.amazon.co.jp/HIFI-WALKER-Resolution-Headphones-Attenuation/dp/B07CXLCKHJ I've had these for a few months now and noticed only two issues, both of which have been easy to resolve: - The stock silicone tips are rather stiff, these quality IEMs deserve better tips. If you don't have higher quality (JVC, Sennheiser, Ultimate Ears, ...) tips at hand, I'd recommend spending a few bucks more for these comfy and good sounding "gel" tips: https://www.ebay.com/sch/i.html?_nkw=sennheiser+cx+gel+tip - The stock cable is a bit springy and lacks a chin slider, which is particularly bothersome if you want to wear the cable over your ears. Solution: just use the twist tie that comes with the IEMs to build yourself a nice DIY chin slider: Edit: newer revision seems to have a chin slider: https://www.superbestaudiofriends.o...hifi-walker-a1-modded.6689/page-2#post-220045 Now, without further ado, here's the measured stock frequency response: Not all that impressive. V-shaped response with boosted bass and a sizeable treble spike, typical of many DD IEMs. Which prompts us to craft a little DIY- micropore damping filter, 2mm wide strips criss-cross on top of the nozzle: (If you don't have 3M micropore tape, you can get it e.g. from here: https://www.amazon.com/3m-Micropore-Medical-Tape-Roll/dp/B0052ELW42/) And the result: (red = stock, blue = micropore) Much better! This is a warm / bassy / downsloping response, with significantly smoother treble than stock. If you're a basshead, or primarily plan to use these in noisy surroundings, you might want to consider stopping at this point. However, if you're looking for a more neutral response, you'll need a thin and sharp needle to pierce the front vent mesh: (Important: make sure your needle is really sharp, as not to dislodge, but actually pierce the mesh beneath the vent!) And the result: (red = stock, green = micropore + pierced front vent) Summary: The HIFI WALKER A1 are very easy to mod and offer stellar sound quality when modded. Compared to the $350 JVC FD01, the fully modded HW A1 fall just a tiny bit short in bass dynamics, detail resolution and treble extension. However, the transition from mid to high range is even a tad smoother on the HW A1 and timbre is similarly excellent on both IEMs to my ears. Bottom line, these offer at least 90% of the JVC FD01's sound quality overall, at 15% of the cost. Highly recommended!